Organic matter and pyrite in shale deposited in reduction environment，which are easy to be oxidized and dissolved. Oxidation is useful to the reform of the seepage channels of shale matrix，but its influence on the stress sensitivity of permeability of shale fracture is not clear. Artificial fractured samples were imbibed in distilled water or 15% oxidation liquid for 24，48，and 72 h respectively. Samples permeability were measured after the samples were dried. The stress sensitivity of the samples that soaked for 72 h were evaluated. Meanwhile，the ion type and concentration of the solution were tested，and the change of shale composition and structure before and after oxidation were characterized by X-ray diffraction（XRD）and scan electron microscope（SEM）. Results show that the permeability of the samples soaked in distilled water is increased by 0.42-6.15 times and the stress sensitivity coefficients range from 0.514 to 0.587. The permeability of rock samples soaked in the oxidation fluid is increased by 5.53-65.45 times，while the stress sensitivity coefficients range from 0.482 to 0.517. Ion analysis and XRD test results show that the oxidation can significantly reduce the content of dolomite and calcite，and pyrite even disappears completely.But the content of clay mineral，quartz and feldspar remains unchanged.It means that selective oxidative dissolution occurs on the fracture plane. The section observation and SEM image of the sample confirm that oxidation fluid infiltrates along the crack and the lamellation，inducing and expanding cracks and improving micro-and nano porosity.It is proved that the oxidation results in the expansion of pore and crack in shale. Selective oxidative dissolution of minerals on the fracture plane and the consequent expansion of pore and crack caused by oxidation，which helps to remain relatively high flow capacity during fracture closure and reduce the stress sensitivity damage.